Company · Ownership research

MPLX LP MPLX

CIK 0001552000 · CUSIP 55336V100

Insider tradingInitial holdingsInstitutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 55336V100 (MPLX), not CUSIP 55336V900 (MPLX), CUSIP 55336V950 (MPLX), and does not merge CUSIPs.
This page lists the top 20 of 577 rows by value; the complete set is available through the API.
Some filings reported values in thousands; those figures were scaled ×1000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value
#ManagerValueManager weightChange vs priorSource

Showing 20 / 577 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions
577
Cancelled or null records excluded
Disclosed shares
210,095,600
Not deduplicated across managers
Disclosed value
$10.50B
Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

MPLX LP · Q3 2025

Explore all 577 reporting institutions.

This page includes 20 of 577 reporting institutions. Sign in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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{"cusip":"55336V100","quarter":"2025Q3","type":"positions","page_size":100}

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.